1. Field of the Invention
The present invention relates to an endoscope apparatus including an insertion part to be inserted into the body, and particularly, to a wiring connection structure inside the distal end of an insertion part.
2. Description of the Related Art
In the related art, an endoscope system that observes a tissue within a body cavity is widely known, and an electronic endoscope system that images a part to be observed in the body cavity using an imaging element to obtain a normal image, and displays the normal image on a monitoring screen has been widely put into practical use.
The above-described endoscope system includes an insertion part to be inserted into the body. A curvable part is provided in the vicinity of a distal end of the insertion part, and the curvable part is curved in any of the vertical and horizontal directions by rotational manipulation of a manipulating knob provided at a manipulating part at the grip of an endoscope body. Thereby, the insertability to the inside of the body of a patient can be made smooth, the distal end of the insertion part can be turned in a desired direction within the body cavity, and an image of a desired part to be observed can be captured.
A multi-conductor cable that bundles signal wiring lines connected to a light guide for guiding illumination light and an imaging element that captures an observation image is loosely inserted inside the insertion part, and for example, a CCD (Charge Coupled Device) serving as the imaging element is provided in the form of a bare chip on which packaging is not performed, inside the distal end of the insertion part. An electrode on the chip is connected to a wiring pattern formed on a circuit board, and individual signal lines in the multi-conductor cable provided to extend within the insertion part are connected to the wiring pattern of the circuit board by soldering or the like.
Here, the curvable part of the insertion part is inserted into the body as described above and is curved in various shapes. At this time, as a bending force or pulling force is applied to the multi-conductor cable provided to extend within the insertion part, there is a concern that a force may be applied to a portion connected to the wiring pattern of the circuit board, and a signal wiring line may separate from the wiring pattern of the circuit board.
Therefore, for example, JP2009-89924A suggests that a combed elastic member is provided in the vicinity of a portion of the signal wiring line connected with the circuit board so as to be entangled in a signal wiring line, thereby allowing expansion and contraction against the pulling of the insertion part in the longitudinal direction. Additionally, JP2009-89925A suggests providing an elasticity imparting unit that imparts elasticity to a multi-conductor cable, within a manipulating part of an endoscope body.